functor-combo-0.0.4: Functor combinators with tries & zippers
FunctorCombo.LocT
Description
Synopsis
type Context t = [Der (PF t) t]Source
Context for a regular type
type LocT t = (Context t, t)Source
Location for a regular type -- a zipper
up :: (Regular t, Holey (PF t)) => LocT t -> LocT tSource
Move upward. Error if empty context.
up' :: (Regular t, Holey (PF t)) => LocT t -> Maybe (LocT t)Source
Variant of up. Nothing if empty context.
up
Nothing
down :: (Regular t, Holey (PF t)) => LocT t -> PF t (LocT t)Source